Any clue guys what is the reason of below error after upgrading to 4.4.1?

The log entry was triggered by a guest

Guests 
Just now

The URL of page the error occurred on was https://carnity.com/forums/topic/12090-engine-oil-lifespan-in-time

 

Error: ErrorException: Object of class stdClass could not be converted to string in /home/carnity/public_html/carnity.com/system/Helpers/Form/Form.php:483
Stack trace:
#0 /home/carnity/public_html/carnity.com/system/Helpers/Form/Form.php(483): IPS\IPS::errorHandler(4096, 'Object of class...', '/home/carnity/p...', 483, Array)
#1 /home/carnity/public_html/carnity.com/system/Content/Item.php(4200): IPS\Helpers\_Form->customTemplate(Array)
#2 /home/carnity/public_html/carnity.com/system/Theme/Theme.php(840) : eval()'d code(3908): IPS\Content\_Item->commentForm()
#3 /home/carnity/public_html/carnity.com/system/Theme/SandboxedTemplate.php(61): IPS\Theme\class_forums_front_topics->topic(Object(IPS\forums\Topic), Array, NULL, Array, NULL, NULL, Array)
#4 /home/carnity/public_html/carnity.com/applications/forums/modules/front/forums/topic.php(434): IPS\Theme\_SandboxedTemplate->__call('topic', Array)
#5 /home/carnity/public_html/carnity.com/system/Dispatcher/Controller.php(96): IPS\forums\modules\front\forums\_topic->manage()
#6 /home/carnity/public_html/carnity.com/system/Content/Controller.php(50): IPS\Dispatcher\_Controller->execute()
#7 /home/carnity/public_html/carnity.com/applications/forums/modules/front/forums/topic.php(39): IPS\Content\_Controller->execute()
#8 /home/carnity/public_html/carnity.com/system/Dispatcher/Dispatcher.php(152): IPS\forums\modules\front\forums\_topic->execute()
#9 /home/carnity/public_html/carnity.com/index.php(13): IPS\_Dispatcher->run()
#10 {main} in /home/carnity/public_html/carnity.com/system/Theme/SandboxedTemplate.php:65
Stack trace:
#0 /home/carnity/public_html/carnity.com/applications/forums/modules/front/forums/topic.php(434): IPS\Theme\_SandboxedTemplate->__call('topic', Array)
#1 /home/carnity/public_html/carnity.com/system/Dispatcher/Controller.php(96): IPS\forums\modules\front\forums\_topic->manage()
#2 /home/carnity/public_html/carnity.com/system/Content/Controller.php(50): IPS\Dispatcher\_Controller->execute()
#3 /home/carnity/public_html/carnity.com/applications/forums/modules/front/forums/topic.php(39): IPS\Content\_Controller->execute()
#4 /home/carnity/public_html/carnity.com/system/Dispatcher/Dispatcher.php(152): IPS\forums\modules\front\forums\_topic->execute()
#5 /home/carnity/public_html/carnity.com/index.php(13): IPS\_Dispatcher->run()
#6 {main}

Backtrace

#0 /home/carnity/public_html/carnity.com/system/Theme/SandboxedTemplate.php(71): IPS\_Log::log(Object(Error), 'template_error')
#1 /home/carnity/public_html/carnity.com/applications/forums/modules/front/forums/topic.php(434): IPS\Theme\_SandboxedTemplate->__call('topic', Array)
#2 /home/carnity/public_html/carnity.com/system/Dispatcher/Controller.php(96): IPS\forums\modules\front\forums\_topic->manage()
#3 /home/carnity/public_html/carnity.com/system/Content/Controller.php(50): IPS\Dispatcher\_Controller->execute()
#4 /home/carnity/public_html/carnity.com/applications/forums/modules/front/forums/topic.php(39): IPS\Content\_Controller->execute()
#5 /home/carnity/public_html/carnity.com/system/Dispatcher/Dispatcher.php(152): IPS\forums\modules\front\forums\_topic->execute()
#6 /home/carnity/public_html/carnity.com/index.php(13): IPS\_Dispatcher->run()
#7 {main}

 

On the surface my first guess would be a modified topic reply template. I'd test with a custom theme as a guest and with the default theme to see if you can reproduce the issue, and if using the default them resolves it. If so, then your solution would be to update your custom theme for 4.4 compatibility.

Thanks @bfarber any clue which exact template file I need to check and revert...?

I can't be certain from the error itself. It may also not be a theme issue, but rather a custom plugin issue. I would suggest running the support tool and clicking the button to disable all third party things, and then work your way back from there. If that resolves it, restore your theme. If it's still ok enable one plugin and test again. And then continue with that process until you find exactly what is breaking the form.